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Replacing Leaking Compression Fittings


I had a new in-floor heat system installed 9 years ago and the fittings on these manifolds (see pics) were not installed well and have been leaking and are getting worse and worse. I want to fix this issue which I'm guessing means throwing away parts of this set-up (scaled-up and corroded) and using new parts. My questions are:

* Am I just changing out the compression fittings on the top of the manifold? Or do you think other parts will need to be replaced.
* Do these compression fittings thread into the manifold?
* Where do I buy fittings like these and what are they called?
* See the "Supply Side" picture: "A" is a bleeder valve right? "B" is a hose nipple, but there isn't a valve between that and the manifold. I don't understand. It would be nice to have a valve here for when I fill it back up with water. Or is there a one-way valve between the hose nipple and the manifold.
* Should I be cutting off the 1/2" PEX and starting on a "fresher" piece
* How much torque on the compression fitting to get no leaks?

Thanks guys!



    EBEBRATT-Ed Member Posts: 15,613
    Probably need to find out who the mfg. is or buy all new parts.

    Is there antifreeze in the system??
  • castover
    castover Member Posts: 17
    No antifreeze - just water. The manufacturer is Rehau. After poking around on the internet I'm thinking it would be best to just purchase all new equipment right of the tape measure (~$200). Can someone answer what "B" is in the top picture? Is there a one way valve between "B" and the manifold or what?
  • hot_rod
    hot_rod Member Posts: 22,254
    If you don't plan on putting zone actuators, and don't need the flow indicators, buy or build a copper manifold with a couple 3/4 X 1/2" tees, and 1/2 pex crimp fittings. Add a couple 1/2 ball valves if you need to balance the circuits.

    Add a couple Webstone valves at the end for purging, probably less than 100 bucks.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream